Sulfur-containing polymers are known to be well-suited for use in aerospace sealants due to their fuel resistant nature upon crosslinking. Such crosslinking can be carried out, for example, by reaction of a thiol-terminated sulfur-containing compound with an epoxy resin, generally in the presence of an amine accelerator as described in U.S. Pat. No. 5,912,319 (Zook et al.). A desirable combination of properties for aerospace sealants, which is difficult to obtain, is the combination of long application time (i.e., the time during which the sealant remains usable) and short curing time (the time required to reach a predetermined strength).
In other technologies, photochemical generation of bases may be useful for a variety of polymerization reactions. For example, photochemically generated bases may be useful for catalyzing epoxide homopolymerization, Michael additions, and thiol- or polyol-isocyanate reactions. Japanese Patent Application Publication JP2009-126974 describes a thiol-epoxide reaction catalyzed by a photogenerated base.